# Relationship history for MSHA mine 4604290

Current hierarchy: **Bohmer & Associates → North Fork Coal Company Inc → No 1 Mine**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** North Fork Coal Company Inc → No 1 Mine; 1974-09-10 to 1976-02-06; source msha-controller-operator-history
- **controller_controls_mine:** Mullens Junior L → No 1 Mine; 1974-09-10 to 1976-02-06; source msha-controller-operator-history
- **controller_controls_operator:** Mullens Junior L → North Fork Coal Company Inc; 1974-09-10 to 1976-02-06; source msha-controller-operator-history
- **operator_operates_mine:** North Fork Coal Company Inc → No 1 Mine; 1976-02-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bohmer & Associates → No 1 Mine; 1976-02-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bohmer & Associates → North Fork Coal Company Inc; 1976-02-07 to current/open; source msha-controller-operator-history